Buggy code:
public class RequestListenerInterface { private static final Map < String , RequestListenerInterface > interfaces = Collections . synchronizedMap ( new HashMap < String , RequestListenerInterface > ( ) ) ; private static final Logger log = LoggerFactory . getLogger ( RequestListenerInterface . class ) ; public static final RequestListenerInterface forName ( final String interfaceName ) { } private Method method ; private final String name ; private boolean includeRenderCount = true ; private boolean renderPageAfterInvocation = true ; final Class < ? extends IRequestListener > listenerInterfaceClass ; public RequestListenerInterface ( final Class < ? extends IRequestListener > listenerInterfaceClass ) { } public Class < ? extends IRequestListener > getListenerInterfaceClass ( ) { } public RequestListenerInterface setIncludeRenderCount ( boolean includeRenderCount ) { } public boolean isIncludeRenderCount ( ) { } public RequestListenerInterface setRenderPageAfterInvocation ( boolean renderPageAfterInvocation ) { } public boolean isRenderPageAfterInvocation ( ) { } public final Method getMethod ( ) { } public final String getName ( ) { } public final void invoke ( final IRequestableComponent rcomponent ) { } public final void invoke ( final IRequestableComponent rcomponent , final Behavior behavior ) { } private void internalInvoke ( final Component component , final Object target ) { Boolean frozen = null ; Page page = component . getPage ( ) ; if ( isAjax ( component ) ) { frozen = page . setFreezePageId ( true ) ; } <START_BUG> if ( page . isStateless ( ) ) { <END_BUG> page . internalInitialize ( ) ; } try { method . invoke ( target ) ; } catch ( InvocationTargetException e ) { if ( ( ( ( e . getTargetException ( ) ) instanceof ReplaceHandlerException ) || ( ( e . getTargetException ( ) ) instanceof AuthorizationException ) ) || ( ( e . getTargetException ( ) ) instanceof WicketRuntimeException ) ) { throw ( ( RuntimeException ) ( e . getTargetException ( ) ) ) ; } throw new WicketRuntimeException ( ( ( ( ( ( ( ( ( "Method<seq2seq4repair_space>" + ( method . getName ( ) ) ) + "<seq2seq4repair_space>of<seq2seq4repair_space>" ) + ( method . getDeclaringClass ( ) ) ) + "<seq2seq4repair_space>targeted<seq2seq4repair_space>at<seq2seq4repair_space>" ) + target ) + "<seq2seq4repair_space>on<seq2seq4repair_space>component<seq2seq4repair_space>" ) + component ) + "<seq2seq4repair_space>threw<seq2seq4repair_space>an<seq2seq4repair_space>exception" ) , e ) ; } catch ( Exception e ) { throw new WicketRuntimeException ( ( ( ( ( ( ( ( ( "Method<seq2seq4repair_space>" + ( method . getName ( ) ) ) + "<seq2seq4repair_space>of<seq2seq4repair_space>" ) + ( method . getDeclaringClass ( ) ) ) + "<seq2seq4repair_space>targeted<seq2seq4repair_space>at<seq2seq4repair_space>" ) + target ) + "<seq2seq4repair_space>on<seq2seq4repair_space>component<seq2seq4repair_space>" ) + component ) + "<seq2seq4repair_space>threw<seq2seq4repair_space>an<seq2seq4repair_space>exception" ) , e ) ; } finally { if ( frozen != null ) { page . setFreezePageId ( frozen ) ; } } } private boolean isAjax ( Component component ) { } public void register ( ) { } @ Override public String toString ( ) { } private final void registerRequestListenerInterface ( final RequestListenerInterface requestListenerInterface ) { } public static Collection < RequestListenerInterface > getRegisteredInterfaces ( ) { } }

Fix:
if ( ! ( page . isInitialized ( ) ) ) {